Wang Kai, Yang Yi, Zhang Tian C, Liang Ying, Wang Qingguo
School of Architecture and Environmental Engineering, Sichuan University Chengdu 610041 P. R. China
Engineering & Research Incorporation Limited Wuhan 430223 P. R. China.
RSC Adv. 2019 Jun 5;9(31):17664-17673. doi: 10.1039/c9ra01671f. eCollection 2019 Jun 4.
Magnetic Co-doped FeO@FeOOH nanocomposites were prepared in one step using the hydrothermal synthesis process for catalyzing peroxymonosulfate (PMS) to degrade refractory methylene blue (MB) at a wide pH range (3.0-10.0). The catalysts' physiochemical properties were characterized by different equipment; Fe/Fe and Co/Co were confirmed to coexist in the nanocomposite by X-ray photoelectron spectroscopy. The nanocomposite effectively catalyzed PMS's decoloration (99.2%) and mineralization (64.7%) of MB. The formation of Co/Fe-OH complexes at the surface of nanoparticles was proposed to facilitate heterogeneous PMS activation. Compared with the observation for FeO@FeOOH, the pseudo-first-order reaction constant was enhanced by 36 times due to Co substitution (0.1620 min 0.0045 min), which was assigned to the redox recycle of Fe/Fe and Co/Co in Co-doped FeO@FeOOH. Besides, the catalyst could be easily reused by magnetic separation and exhibited relatively long-term stability.
采用水热合成法一步制备了磁性共掺杂FeO@FeOOH纳米复合材料，用于催化过一硫酸盐（PMS）在较宽pH范围（3.0 - 10.0）下降解难降解的亚甲基蓝（MB）。用不同设备对催化剂的理化性质进行了表征；通过X射线光电子能谱证实纳米复合材料中Fe/Fe和Co/Co共存。该纳米复合材料有效地催化了PMS对MB的脱色（99.2%）和矿化（64.7%）。提出在纳米颗粒表面形成Co/Fe - OH络合物有助于非均相PMS活化。与FeO@FeOOH的情况相比，由于Co取代，准一级反应常数提高了36倍（从0.0045 min提高到0.1620 min），这归因于共掺杂FeO@FeOOH中Fe/Fe和Co/Co的氧化还原循环。此外，该催化剂可通过磁分离轻松重复使用，并表现出相对长期的稳定性。
